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Hello,
I study Horizontal Fragmentation in distributed data bases. I see phrase simple predicates.
C#
Given R(A1, A2, .., An), a simple predicate pj is defined as "pj: Ai θ value", where θ є {=, <, ≤, >, ≥, ≠} and value є Di, where Di is the domain of Ai.
–
Examples:
PNAME = "Maintenance"
BUDGET ≤ 200000


C#
A set of simple predicates may have two key properties

1. Completeness of Simple Predicates is
C#
same minterm fragment have the same probability of being accessed by any application.

2. Minimality of Simple Predicates is
C#
if p influences how fragmentation is performed (i.e., causes a fragment f to be further fragmented into fi and fj), then there should be at least one application that accesses fi and fj differently.

But, I need an example, on a simple fragmented table.
I can't understand them!
What is probability in Completeness or What is differently access in Minimality?
Thanks

What I have tried:

Understanding Completeness of Simple Predicates and Minimality of Simple Predicates in Horizontally fragmentation in Distributed data bases by an example.
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